This patch introduces netfilter hooks for solving the problem that
conntrack couldn't record both inner flows and outer flows.
Signed-off-by: proelbtn <contact@xxxxxxxxxxxx>
---
net/ipv6/seg6_iptunnel.c | 69 +++++++++++++++++++++--
net/ipv6/seg6_local.c | 116 +++++++++++++++++++++++++++------------
2 files changed, 143 insertions(+), 42 deletions(-)
diff --git a/net/ipv6/seg6_iptunnel.c b/net/ipv6/seg6_iptunnel.c
index 897fa59c47de..09870ef41768 100644
--- a/net/ipv6/seg6_iptunnel.c
+++ b/net/ipv6/seg6_iptunnel.c
@@ -26,6 +26,8 @@
#ifdef CONFIG_IPV6_SEG6_HMAC
#include <net/seg6_hmac.h>
#endif
+#include <net/lwtunnel.h>
+#include <net/netfilter/nf_conntrack.h>
static size_t seg6_lwt_headroom(struct seg6_iptunnel_encap *tuninfo)
{
@@ -295,25 +297,33 @@ static int seg6_do_srh(struct sk_buff *skb)
ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
skb_set_transport_header(skb, sizeof(struct ipv6hdr));
+ nf_reset_ct(skb);
return 0;
}
-static int seg6_input(struct sk_buff *skb)
+static int seg6_input_finish(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
+{
+ return dst_input(skb);
+}
+
+static int seg6_input_core(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
{
struct dst_entry *orig_dst = skb_dst(skb);
struct dst_entry *dst = NULL;
- struct seg6_lwt *slwt;
+ struct seg6_lwt *slwt = NULL;
int err;
+ slwt = seg6_lwt_lwtunnel(orig_dst->lwtstate);
+
err = seg6_do_srh(skb);
if (unlikely(err)) {
kfree_skb(skb);
return err;
}
- slwt = seg6_lwt_lwtunnel(orig_dst->lwtstate);
-
preempt_disable();
dst = dst_cache_get(&slwt->cache);
preempt_enable();
@@ -337,10 +347,35 @@ static int seg6_input(struct sk_buff *skb)
if (unlikely(err))
return err;
- return dst_input(skb);
+ if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
+ return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
+ dev_net(skb->dev), NULL, skb, NULL,
+ skb_dst(skb)->dev, seg6_input_finish);
+
+ return seg6_input_finish(dev_net(skb->dev), NULL, skb);
}
-static int seg6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
+static int seg6_input(struct sk_buff *skb)
+{
+ int proto;
+
+ if (skb->protocol == htons(ETH_P_IPV6))
+ proto = NFPROTO_IPV6;
+ else if (skb->protocol == htons(ETH_P_IP))
+ proto = NFPROTO_IPV4;
+ else
+ return -EINVAL;
+
+ if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
+ return NF_HOOK(proto, NF_INET_POST_ROUTING, dev_net(skb->dev),
+ NULL, skb, NULL, skb_dst(skb)->dev,
+ seg6_input_core);
+
+ return seg6_input_core(dev_net(skb->dev), NULL, skb);
+}
+
+static int seg6_output_core(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
{
struct dst_entry *orig_dst = skb_dst(skb);
struct dst_entry *dst = NULL;
@@ -387,12 +422,34 @@ static int seg6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
if (unlikely(err))
goto drop;
+ if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
+ return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk, skb,
+ NULL, skb_dst(skb)->dev, dst_output);
+
return dst_output(net, sk, skb);
drop:
kfree_skb(skb);
return err;
}
+static int seg6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+ int proto;
+
+ if (skb->protocol == htons(ETH_P_IPV6))
+ proto = NFPROTO_IPV6;
+ else if (skb->protocol == htons(ETH_P_IP))
+ proto = NFPROTO_IPV4;
+ else
+ return -EINVAL;
+
+ if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
+ return NF_HOOK(proto, NF_INET_POST_ROUTING, net, sk, skb, NULL,
+ skb_dst(skb)->dev, seg6_output_core);
+
+ return seg6_output_core(net, sk, skb);
+}
+
static int seg6_build_state(struct net *net, struct nlattr *nla,
unsigned int family, const void *cfg,
struct lwtunnel_state **ts,
diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c
index 60bf3b877957..f29cdd753a37 100644
--- a/net/ipv6/seg6_local.c
+++ b/net/ipv6/seg6_local.c
@@ -30,6 +30,8 @@
#include <net/seg6_local.h>
#include <linux/etherdevice.h>
#include <linux/bpf.h>
+#include <net/netfilter/nf_conntrack.h>
+#include <net/lwtunnel.h>
#define SEG6_F_ATTR(i) BIT(i)
@@ -413,12 +415,33 @@ static int input_action_end_dx2(struct sk_buff *skb,
return -EINVAL;
}
+static int input_action_end_dx6_finish(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
+{
+ struct dst_entry *orig_dst = skb_dst(skb);
+ struct seg6_local_lwt *slwt = NULL;
+ struct in6_addr *nhaddr = NULL;
+
+ slwt = seg6_local_lwtunnel(orig_dst->lwtstate);
+
+ /* The inner packet is not associated to any local interface,
+ * so we do not call netif_rx().
+ *
+ * If slwt->nh6 is set to ::, then lookup the nexthop for the
+ * inner packet's DA. Otherwise, use the specified nexthop.
+ */
+ if (!ipv6_addr_any(&slwt->nh6))
+ nhaddr = &slwt->nh6;
+
+ seg6_lookup_nexthop(skb, nhaddr, 0);
+
+ return dst_input(skb);
+}
+
/* decapsulate and forward to specified nexthop */
static int input_action_end_dx6(struct sk_buff *skb,
struct seg6_local_lwt *slwt)
{
- struct in6_addr *nhaddr = NULL;
-
/* this function accepts IPv6 encapsulated packets, with either
* an SRH with SL=0, or no SRH.
*/
@@ -429,55 +452,64 @@ static int input_action_end_dx6(struct sk_buff *skb,
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
goto drop;
- /* The inner packet is not associated to any local interface,
- * so we do not call netif_rx().
- *
- * If slwt->nh6 is set to ::, then lookup the nexthop for the
- * inner packet's DA. Otherwise, use the specified nexthop.
- */
-
- if (!ipv6_addr_any(&slwt->nh6))
- nhaddr = &slwt->nh6;
-
skb_set_transport_header(skb, sizeof(struct ipv6hdr));
+ nf_reset_ct(skb);
- seg6_lookup_nexthop(skb, nhaddr, 0);
+ if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
+ return NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING,
+ dev_net(skb->dev), NULL, skb, NULL,
+ skb_dst(skb)->dev, input_action_end_dx6_finish);
- return dst_input(skb);
+ return input_action_end_dx6_finish(dev_net(skb->dev), NULL, skb);
drop:
kfree_skb(skb);
return -EINVAL;
}
-static int input_action_end_dx4(struct sk_buff *skb,
- struct seg6_local_lwt *slwt)
+static int input_action_end_dx4_finish(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
{
+ struct dst_entry *orig_dst = skb_dst(skb);
+ struct seg6_local_lwt *slwt = NULL;
struct iphdr *iph;
__be32 nhaddr;
int err;
- if (!decap_and_validate(skb, IPPROTO_IPIP))
- goto drop;
-
- if (!pskb_may_pull(skb, sizeof(struct iphdr)))
- goto drop;
-
- skb->protocol = htons(ETH_P_IP);
+ slwt = seg6_local_lwtunnel(orig_dst->lwtstate);
iph = ip_hdr(skb);
-
nhaddr = slwt->nh4.s_addr ?: iph->daddr;
skb_dst_drop(skb);
- skb_set_transport_header(skb, sizeof(struct iphdr));
-
err = ip_route_input(skb, nhaddr, iph->saddr, 0, skb->dev);
- if (err)
- goto drop;
+ if (err) {
+ kfree_skb(skb);
+ return -EINVAL;
+ }
return dst_input(skb);
+}
+static int input_action_end_dx4(struct sk_buff *skb,
+ struct seg6_local_lwt *slwt)
+{
+ if (!decap_and_validate(skb, IPPROTO_IPIP))
+ goto drop;
+
+ if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+ goto drop;
+
+ skb->protocol = htons(ETH_P_IP);
+ skb_set_transport_header(skb, sizeof(struct iphdr));
+ nf_reset_ct(skb);
+
+ if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
+ return NF_HOOK(NFPROTO_IPV4, NF_INET_PRE_ROUTING,
+ dev_net(skb->dev), NULL, skb, NULL,
+ skb_dst(skb)->dev, input_action_end_dx4_finish);
+
+ return input_action_end_dx4_finish(dev_net(skb->dev), NULL, skb);
drop:
kfree_skb(skb);
return -EINVAL;
@@ -645,6 +677,7 @@ static struct sk_buff *end_dt_vrf_core(struct sk_buff *skb,
skb_dst_drop(skb);
skb_set_transport_header(skb, hdrlen);
+ nf_reset_ct(skb);
return end_dt_vrf_rcv(skb, family, vrf);
@@ -1078,22 +1111,18 @@ static void seg6_local_update_counters(struct seg6_local_lwt *slwt,
u64_stats_update_end(&pcounters->syncp);
}
-static int seg6_local_input(struct sk_buff *skb)
+static int seg6_local_input_core(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
{
struct dst_entry *orig_dst = skb_dst(skb);
+ struct seg6_local_lwt *slwt = NULL;
struct seg6_action_desc *desc;
- struct seg6_local_lwt *slwt;
unsigned int len = skb->len;
int rc;
- if (skb->protocol != htons(ETH_P_IPV6)) {
- kfree_skb(skb);
- return -EINVAL;
- }
-
slwt = seg6_local_lwtunnel(orig_dst->lwtstate);
- desc = slwt->desc;
+ desc = slwt->desc;
rc = desc->input(skb, slwt);
if (!seg6_lwtunnel_counters_enabled(slwt))
@@ -1104,6 +1133,21 @@ static int seg6_local_input(struct sk_buff *skb)
return rc;
}
+static int seg6_local_input(struct sk_buff *skb)
+{
+ if (skb->protocol != htons(ETH_P_IPV6)) {
+ kfree_skb(skb);
+ return -EINVAL;
+ }
+
+ if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
+ return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_IN,
+ dev_net(skb->dev), NULL, skb, skb->dev, NULL,
+ seg6_local_input_core);
+
+ return seg6_local_input_core(dev_net(skb->dev), NULL, skb);
+}
+
static const struct nla_policy seg6_local_policy[SEG6_LOCAL_MAX + 1] = {
[SEG6_LOCAL_ACTION] = { .type = NLA_U32 },
[SEG6_LOCAL_SRH] = { .type = NLA_BINARY },
--
2.25.1
